Labour has benefited from the slow decline of Liberal Democrats and the Conservatives from the collapse of the Brexit Party vote.
If we extrapolate this to seat shares, assuming a uniform swing across the country (which is a big assumption) then it shows a Conservative majority of 84 seats in Great Britannia.
At this stage of the 2017 election campaign, the Conservative lead over Labour in voting intentions was about 7% so the campaign dynamics we observed in 2017 are not the same as now.
The air was sucked out of the campaign to some extent by the YouGov MRP (multi-level regression post-stratification) poll which uses a very large sample of more than 100,000 respondents and was successful in predicting the 2017 general election.
In the present election campaign, it predicts a 68-seat Conservative majority.
But as the YouGov team explained on their website, a problem with this method is that it spectacularly increases the margins of error for the seat predictions.
At least three things can go wrong in predicting the outcome of the election at this stage. They are differential turnout, tactical voting, and late campaign dynamics in party support.
To probe turnout and tactical voting in more detail we can look at the YouGov poll for the Sunday Times published on December 1. This put the Conservatives 9% ahead of Labour in voting intentions, predicting that the party will win 43% of the vote compared with Labour’s 34%.
These figures are, of course, subject to the usual margin of error of about plus or minus 3%.
Boris Johnson
...pro-Brexit British prime minister, succeeding no-Brexit Theresa May. BoJo is noted as much for his sparkling personality and his hair as for his Conservative policies....is targeting Labour Leave constituencies in the Midlands and North with the hope of turning lifelong Labour voters into Conservatives.
Undoubtedly, many of these will be cross-pressured by their dislike of Jeremy Corbyn and Labour’s ambivalence on the Brexit issue on the one hand, and a traditional dislike of the Conservatives on the other. An easy way to solve their problem is for them not to vote at all. If so, this would reduce the chances of the Conservatives capturing these seats.
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